1. Field of the Invention
This invention relates to a method of controlling a building against an earthquake, comprising the steps of utilizing an earthquake observing network and a communication network when an earthquake happened to adjust positively the rigidity of a building itself by a control device or giving exciting force for cancelling a seismic oscillation input to the building in the opposite direction, thereby preventing the building from damages due to resonance phenomena.
2. Description of the Prior Art
Conventionally, in earthquake-proof designs of multistoried buildings, important structures or the like have been calculated the movement of foundation and the response of buildings when on earthquake happened to carry out the dynamic design for checking the safety.
For the earthquake-proof method are employed a quake avoiding or reducing method in which laminated rubber supports and dampers are interposed between the building and the foundation, a method of consuming the seismic energy through the breakage of non-main members of building contituents, a method of providing slits in walls, pillars or the like to adjust the building to the optimum rigidity.
Also, the present applicant has already developed the quake avoiding and resisting system which controls a trigger device interposed connectively or releasably between the building and the foundation side base by utilizing the earthquake observing network and communication network (see Japanese Patent Laid-Open No. Sho 62-63776).
Now, the safety of buildings designed by the current quake resisting design method in an earthquake is confirmed on the basis of the fundamental concept that the absorbing energy due to hysteresis characteristics accompanied by the plasticization of structure exceeds the seismic energy acting on the structure. However, the above case presents a problem of reliability on hysteresis loop characteristics.
Further, all conventional methods except for the method by said application give the quake resisting structures passive to the natural external forces such as earthquake, wind or the like so that the resonance phenomena to an uncertain input of earthquake cannot be avoided since a building has a specific natural frequency.